Solar Impulse 2 is one step closer to reaching its goal of becoming the first airplane to circumnavigate the world without using a single drop of fuel.

On Thursday, it completed the 11th leg of its journey by landing at Tulsa International Airport around 11:15pm local time. Bertrand Piccard piloted the plane during the 18-hour trip and was greeted with a lot of excitement from Tulsa’s mayor and city residents.

It was a stop that came as a surprise to many. The team initially planned on flying from Phoenix, Arizona to Kansas City, Missouri, but were forced to change their route due to high winds in the area. They were faced with three options:

Go to Albuquerque as a first step and set up a mobile hanger to protect Si2

Find a new airport in Tornado Valley with a fixed hanger.

The team settled on option three since stalling the mission would throw off their timeline to fly across the Atlantic and flying to Albuquerque meant putting the plane at a greater risk of damage in a mobile hanger.

After a few calls, the team arranged for Piccard to fly to Tulsa, where American Airlines had agreed to share one of its hangers to house Solar Impulse 2.

The team hopes to soon fly to Lehigh Valley, Pennsylvania, and New York, but the plane’s delicate structure is forcing them to wait for better weather.